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US2636828A
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Silicon nitride-bonded refractory oxide bodies and method of making
Assignee: Unifrax I LLC
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Filing: 1948-02-26
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Granted: 1953-04-28
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Expires: 1968-02-26
Abstract
No abstract record available.
Inventors
- 👤 Kenneth C Nicholson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 21:50
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/622; C04B35/64; C04B35/65
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
87 words
AN ARTICLE OF MANUFACTURE COMPRISING REFRACTORY OXIDIC MATERIAL HELD TOGETHER BY AN INTERSTITIAL SILICON NITRIDE BOND IN WHICH SUBSTANTIALLY ALL THE SILICON IS COMBINED WITH NITROGEN AS SILICON NITRIDE HAVING THE CHEMICAL FORMULA S13N4, SAID SILICON NITRIDE BOND CONTAINING AN AMOUNT OF IRON SUFFICIENT TO EFFECTIVELY PROMOTE THE CONVERSION OF SILICON TO SILICON NITRIDE HAVING THE CHEMICAL FORMULA S13N4, SAID ARTICLE HAVING A MODULUS OF RUPTURE AT ROOM TEMPERATURE OF SEVERAL THOUSAND POUNDS PER SQUARE INCH AND BEING CAPABLE OF RESISTING OXIDATION IN AIR AT ELEVATED TMEPERATURES.
Claim 2
Dependent Claim
87 words
AN ARTICLE OF MANUFACTURE COMPRISING REFRACTORY OXIDIC MATERIAL HELD TOGETHER BY AN INTERSTITIAL SILICON NITRIDE BOND IN WHICH SUBSTANTIALLY ALL THE SILICON IS COMBINED WITH NITROGEN AS SILICON NITRIDE HAVING THE CHEMICAL FORMULA S13N4, SAID SILICON NITRIDE BOND CONTAINING AN AMOUNT OF IRON SUFFICIENT TO EFFECTIVELY PROMOTE THE CONVERSION OF SILICON TO SILICON NITRIDE HAVING THE CHEMICAL FORMULA S13N4, SAID ARTICLE HAVING A MODULUS OF RUPTURE AT ROOM TEMPERATURE OF SEVERAL THOUSAND POUNDS PER SQUARE INCH AND BEING CAPABLE OF RESISTING OXIDATION IN AIR AT ELEVATED TMEPERATURES.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-04-27 | 1956-10-27 | 1957-04-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-04-27 | 1960-10-27 | 1961-04-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-04-27 | 1964-10-27 | 1965-04-28 | $7700.00 | Window Closed / Lapsed |